\documentclass[12pt,oneside]{book}


\RequirePackage{geometry}
\RequirePackage[CJKecglue={\hskip 0pt}]{xeCJK}
\xeCJKsetup{PunctStyle=plain}
\setCJKmainfont[ItalicFont=TW-Kai]{Source Han Serif CN}
\setCJKsansfont{Source Han Sans CN}
\setCJKmonofont{TW-Kai}


\begin{document}
\makeatletter
\renewcommand\title[1]{\def\@title{#1}}
\newcommand\subtitle[1]{\def\@subtitle{#1}}
\renewcommand\author[1]{\def\@author{#1}}
\newcommand\version[1]{\def\@version{#1}}
\renewcommand\date[1]{\def\@date{#1}}

\renewcommand{\today}{\number\year{}年\number\month{}月\number\day{}日}
\subtitle{}
\date{\today}
\version{}

\title{XeLaTex指南}
\author{万泽}
%\subtitle{一个简单的封面}
%\date{\today}
%\version{第四次修订版}

\begin{titlepage}
\newgeometry{left=1cm,right=1cm,top=1cm,bottom=1cm}
\begin{center}
\vspace*{120pt}
{\fontsize{80pt}{40pt}\selectfont\sffamily \@title}

\vspace{40pt}
{\fontsize{40pt}{20pt}\selectfont\sffamily \@subtitle} 

\vspace{200pt}
{\fontsize{40pt}{20pt}\selectfont\sffamily \@author}

\vspace{150pt}
{\fontsize{30pt}{20pt}\selectfont\ttfamily \@date \@version}

\end{center}
\end{titlepage}

\makeatother

\end{document}